Histograms in GeoGebra
1. Select the data (A1:F5).
2. Click on the "One Variable Analysis" button. Click the Analyze button on the popup.
3. Click the "Options" arrow button above the Histogram. (It's in the top right of the applet window)
4. Set Classes Manually - Start = 35 - Width = 5
5. Set the Class Rule to the second option to include the high endpoint.
6. Histogram should be checked under "Show" but also experiment with checking "Frequency Table" and "Frequency Polygon"